Series of structural plug-in components for erection of scaffolding,frameworks or the like



3,429,093 CTION Feb. 25, 1969 A. HUFGARD *A SERIES OF STRUCTURAL PLUG-IN COMPONENTS FOR ERE OF SCAFFOLDING, FRAMEWORKS 'OR THE LIKE Filed Aug. 23, 1966 Sheet /nventorf HJHHDQU 2 MUHHUHHMUUUQHH nga/@g4 F/g5 Fig! Feb. 25, 1969 Filed Aug. 23, 1966 SERIES oF STRUCTURAL T A HUFGARD LUG- OF SCAFFOLDING, FRA

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Inventor:

United States Patent O 3,429,093 SERIES OF STRUCTURAL PLUG-IN COMPO- NENTS FOR ERECTION OF SCAFFOLDING, FRAMEWORKS OR THE LiKE Albert Hufgard, Antoniusweg, 8752 Rottenberg, Germany Filed Aug. 23, 1966, Ser. No. 574,447 U.S. Cl. 52-648 16 Claims Int. Cl. E04h 12/00; A63h 33/08; E04g 1/12 ABSTRACT OF THE DISCLOSURE A series of elements which may be interconnected to form intricate structures without the utilization of intermediate fasteners.

This invention relates to a series `of structural plug-in components for assembly into scaffolding for use in conjunction with the rapid construction of such structures as sheds, weekend cottages or the like. More specifically, this invention is directed to a series of structural plug-in elements for assembly into suitably dimensioned models for architectural and playing purposes.

Heretofore, numerous suggestions have been made for the erection of scaffolding by unit-construction techniques, using standard elements such as building blocks, bar or sectional stock, which may be assembled into structures by inserting the component parts one into another and holding them together by means of connecting elements or couplers such as plug-like members, bolts, clamps or the like.

A considerable drawback of such prior-art arrangements consists in that numerous `auxiliary elements as nut locks, bracket supports, etc. were required to make the structures sufficiently resistant to loading. Moreover, difliculties have sometimes been encounteretd in the mounting of such auxiliary means.

In the case of elements designed for playing purposes, very frequently no provision was made for a suicient Amechanical stability, although it is particularly the structures assembled from toy elements that are often severely stressed by children.

In one prior-art arrangement, plug-in elements are provided which are of approximately elliptical cross-section and are provided with suitably dimensioned apertures in their side walls. The variability of these elements is very limited, as is their load-bearing capacity, when assembled.

To simplify the combinations of assembly, it has also been proposed to employ U-shaped bar members having a plurality of holes in their vertical legs and apertures of a half-hole size in their horizontal legs. Such elements have to be welded together for connection, if they are to be used as hollow sections. Further, brackets and screw couplings are required, if the elements are to be assembled into scaffolding. Elements of this type cannot be inserted one into another, because all of them are identical in cross-section.

Similar difficulties have been encountered in the case of hollow sections having oblong holes or slots in each of their side walls. Although the use of such slotted holes facilitates the relative disposition of the elements as well as the making of screwed connections, special auxiliary means are required, if the elements are to be seriesconnected. In addition, transverse connections could be eected only by placing the elements against each other and screwing them together.

It is accordingly a primary object of this invention to provide a series of structural elements which because of their unique construction and arrangement are highly suited to assembly into scaffolding, frameworks or the like.

ICC

A further object of the invention is to provide a series of plug-in components which can be easily inserted one into another in various directions.

Another object of the invention is to provide a plurality of structural elements of different sizes in which each element of a predetermined size fits into an element of the next larger size.

Still another object is to provide a series of structural elements which are characterized by a relatively high load-bearing capacity.

A further object of the invention is to provide unique coupling means for the structural elements set forth above whereby elements meeting at any desired angle may be easily interconnected.

Still another object is to provide a series of structural plug-in components which can be relatively simply fabricated by various methods and processes, such as casting, injection molding, etc.

According to one feature of the invention, each element in a series of structural elements is of substantially square cross-section. Extending substantially longitudinally through each next-larger element is a square passage or channel whose cross-sectional size Icorresponds to that of the next smaller element so that the latter may be fitted into that next-larger element by inserting it into the passage through that element.

According to a further feature of the invention, at least each next-larger element in the series of elements has formed in its side Walls a plurality of substantially square-shaped `apertures whose size equals substantially that of the inner passage through the respective element. The apertures are arranged in pairs such that the apertures of each pair formed in a first pair of opposed side Walls of the element are disposed in aligned, opposed relationship with respect to each other and in angular, staggered relationship with respect to each pair of apertures formed in a second pair of opposed side walls of the element. Due t0 this arrangement the elements can be plugged together both longitudinally and transversely.

According to another feature, a unique coupling means is provided which permits the elements to be connected at any desired angle.

For playing or model purposes, a structural element constructed in accordance with this invention may be of square cross-section having a width of one inch, for example, with square apertures of 0.5 by 0.5 inch provided in each pair of opposed side walls of the element, so that the next smaller element, which may be also of square cross-section but having a width of 0.5 inch, imay be inserted into the apertures and held in place by plug members or other suitable means to be inserted into and through both the receiving element and the element received. Of course the selection of the size of the elements to be inserted is a function of the shape of cross-section of the receiving elements.

Due to their unique construction and arrangement the elements of the invention may be assembled into frameworks of relatively high load-bearing capacity, with the outer surfaces of the elements respectively lying in one plane so that they may be used `as bearing surfaces for paneling, if desired. It is, however, also possible to dispose the elements closely side by side thereby forming continuous surfaces except for the locating holes and side-wall apertures. Such surfaces may then be used as walls, intermediate bottoms, ceilings, etc.

In addition to the great variety of mounting combinations aiforded by the invention, a further advantage consists in that the elements may be fabricated by such methods as casting or injection molding, without the necessity for insertion of cores into the molds, it only being necessary to provide crossways staggered holeforming means within the molds. Since, according to the invention, the upper and lower edges of the apertures in the side Walls lie in one plane, the central longitudinal passage through the element will, in a way, be automatic-ally formed during the casting or molding operation.:

Connection of transverse cross-bracing as well as of articulated couplers to the main elements at other than right angles may be simply effected by auxiliary elements of suitable cross-section.

Both the main and auxiliary elements may be made from any suitable material, particularly plastics, for example. For playing purposes as well as for the construction of architectural models Plexiglas, a polymeriz-ate made from an `acrylic or methacrylic base, has been found to be particularly suitable, because it is easy to make, particularly by injection molding techniques, in any desired color, and may be cleaned with the usual cleaning agents. This is of great advantage when the elements are intended for playing purposes. Of course other plastics of suitable properties may be also used. Such materials, however, should be sufficiently rigid and as heat-resistant as possible.

For other purposes, particularly for erection of scaffolding subject to high static loading, the elements should prefer-ably be formed of metallic material such as sheet metal, particularly special sheet. Further, provision should be made for larger bearing surfaces to keep the wall thickness of the sheet-metal elements within economical limits. Thus it would be of advantage to bend portions of the sheet-metal material adjacent to the Iapertures and locating holes in the side walls of the main and auxiliary elements inwardly whereby enlarged bearing and guide surfaces would be formed for the elements to be inserted.

In cases in which prefabricated parts are used for construction purposes, the elements of the invention may also be formed of cast concrete. Of course, elements made of concrete require larger tolerances on the insertion than do plastics elements intended for playing `and model purposes. Such prefabricated concrete elements are particularly light in weight and may be iilled up, either partly, as in the connecting zones of assembled elements, or completely, with la suitable material, with or without reinforcements. For this purpose, the concrete elements may be covered with boarding, if desired, which is much easier and simpler to construct than the usual formwork.

Further objects, features and advantages of the invention will become apparent from the following detailed description, when read in conjunction with the drawings, in which FIGURES l through 5 are side and end views of the elements of a series of elements constructed in accordance with the invention, each of the elements being square in cross-section but differing in its crosssectional size from the other elements such that each element of a next smaller size ts into an element of a next larger size;

FIGURE 6 shows an example of a framework assembled from elements of FIGS. 1 through 5;

2FIGURE 7 shows another embodiment of a structural element of the invention which is formed of sheet-metal;

FIGURE 8 shows a coupler which permits the connection of elements at -any desired angle; and

FIGURE 9 is a particular embodiment of part of an element.

As shown in FIGS. 1 and 2, apertures 4 and holes 5 of subst-antially square cross-section are formed in alternate sequence in the side walls of element 1. Each of the apertures and holes formed in one side wall of a pair of opposed side walls is in alignment with an aperture and hole, respetcively, of the same size in the other side wall of the respective pair of opposed side Walls, while equally sized apertures and holes in different pairs of opposed side walls are arranged in staggered relationship, with the upper and lower edges of staggered apertures and holes respectively lying in one plane. Of course, a series of elements may also comprise a larger number of distinct elements than in the present example. As shown, each of the elements 1 and 2 has a channel or passage 6 extending longitudinally through it. As stated above, the cross-sectional size of each structural element and the size of the apertures and holes are so adjusted one to another that each element of a given series of elements may be fitted into the next-larger element of the series.

Due to this arrangement the elements l, 2 and 3 of FIGS. l through 5 may be fitted together both lengthwise and transversely.

An example of an assembled combination of elements is shown in FIG. 6. A longitudinal or end connection between two elements, as 1, may be effected by inserting a smaller element, as 2, into both elements 1. Of course, further sequence elements may be interconnected in the same way, depending upon the prevailing load conditions. Components that have been plugged together in the manner described above, may be held in place by members 3 of suitably shortened length. Advantageously, such short fixing members may be in the nature of clamping or split-taper sleeves so that they may be more or less tightly fitted through suitable ones of aligned apertures in the structural components, after the latter have been plugged together. It should be understood that other suitable connecting or coupling means such as split pins, bolts, etc. may also be used, depending upon the particular shape of the apertures, Frefetably, the connecting members should not project from the planes of the walls of the structural elements. Alternatively, it is also possible to thread the walls of the holes or to insert threaded bushings into the holes for screwing-in of threaded pins.

Although structures made up of such elements exhibit already a remarkable stability, it may become necessary to provide an angularly inclined cross-bracing between the horizontally and vertically extending elements. Further, in certain cases it may also become necessary to provide facilities for connection of inclined roof elements or the like. To permit the connection of such inclined components, irrespective of their degree of inclination, a unique coupling means, generally designated at 7 in FIG. 8, may be used. As shown in this figure, an angular or inclined connection may comprise a short element 2 pivotally attached to a substantially U-shaped bridge member or coupler 7, which in the example shown is of a cross-sectional size that corresponds to that of element 1. This U-shaped coupler may, through the agency of a further connecting element 2, be inserted into an aperture 4 in element 1 at any desired place and fastened by means of a short bar or element 3. Each leg 15 of the U-shaped bridge member 7 is provided with a circular hole which extends transversely through the leg. The diameter of the holes is chosen so that the short element or bar 3 may be slide-tted into and through the holes, thereby forming an axis of rotation about which the short element 2, which is supported on bar 3, may be tilted. In other words, the diameter of the holes corresponds approximately to the diagonal of the cross-sectional area of bar 3.

In a preferred embodiment, each leg 15 may be provided With a square cutout or aperture 9, into which a suitable bearing portion 8 having a suitable through-hole 8 may be inserted. With such an arrangement a further connecting element 2 may be inserted into coupler 7 for other connecting purposes. Each bearing portion 8 may be provided along its periphery with slightly raised, cam-like portions (not specifically shown) or the like so that it may be press-fitted into aperture 9 or 4. In this manner elements 1 may be also assembled into carriage or chassis frames for playing purposes. To this end, bearings 8 may be fitted into opposed apertures 4, whereupon connecting members 3 serving as axles may be inserted through holes 8 in bearings 8. Suitable wheels may then be fitted on the ends of elements 3 and secured to them in any suitable manner.

FIG. 7 shows another embodiment of a structural component which is formed of sheet metal. This element, which is generally designated at 10, is substantially identical to the previously described element 1, so far as its outer shape is concerned. In order to make the walls of apertures 4 and holes 5' suitable for use as guide and bearing surfaces for sequence or intermediate elements when making lengthwise or transverse connections, portions of the sheet-metal material adjacent to the apertures and holes may be bent inwardly to form suitable bearing surfaces.

It should be understood that many other forms of auxiliary elements may be contemplated. An example of such an auxiliary element is shown in FIG. 9. This element comprises two short outer plug-like portions 12 which are spaced apart by and secured in an intermediate or inner portion 13 through which extends a square or circular passage 14. Plugs 12 correspond in their crosssectional size to element 3, whereas the cross-sectional size of inner portion 13 corresponds to that of element 2. Preferably, plugs 12 may be provided with at cam-like portions 12', which upon insertion of the plugs into apertures 4 in element 2 engage in the longitudinal passage 6.

It is thus seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes and/or moditications may be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all the features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described the invention, what is claimed as new and desired to secure by Letters Patent is:

1. A series of structural plug-in components for construction of such structures as scaffolding, frame-works or the like, particularly for playing purposes, comprising a series of elongated elements capable of being plugged together lengthwise and in transverse direction, said elements being substantially square in cross-section but differing one from another in the size of their crosssectional areas, an inner passage through each of said elements with the exception of the element of smallest cross-section in said series of elements, said passage extending longitudinally through its element, a plurality of substantially square-shaped apertures formed in the side walls of at least each element of a respectively next-larger cross-section in said series of elements, said apertures being arranged in pairs in said side walls of said elements such that each pair of apertures formed in a iirst pair of opposed ones of said side walls are disposed in aligned relationship with respect to each other and in angular, staggered relationship with respect to each pair of apertures formed in a second pair of opposed ones of said side walls, each of said apertures in said side Walls of each respective element corresponding in cross-section to the inner passage through said respective element, the upper and lower edges of successive pairs of apertures disposed in angular, staggered relationship lying in a common intersecting plane perpendicular to the major axis of said respective element, and a plurality of openings formed in the side walls of at least the element of largest cross-section in said series for insertion of plugin members such as xing pins, connecting and joint members or the like, said apertures and said openings being arranged in alternate sequence in said side walls of said element, the arrangement being such that each of the elements succeeding the element of largest crosssection in said series is of a cross-sectional size corresponding to that of the inner passage through each element of respectively next-larger cross-section.

2. A series of structural components as claimed and set forth in claim 1, wherein said openings are of substantially square cross-section.

3. A series of structural components as claimed and set forth in claim 1, wherein said elements are formed of sheet-metal material, portions of said material adjacent to said apertures and said openings in lsaid side walls being bent inwardly so as to form bearing and guide surfaces for the elements to be inserted.

4. A series of structural elements as defined and claimed in claim 1, wherein short-length portions of at least the last element in said series of elements are in the nature of plug members spaced apart by an intermediate portion whose cross-section corresponds to that of a preceding element of said series of elements.

5. A series of structural elements according to claim 4, wherein the plug members are provided with slightly raised, cam-like portions.

6. A series of structural elements according to claim 1, wherein short portions of at least the last element in said series of elements are in the nature of clamping sleeves.

7. A series of structural elements as claimed in claim 1, wherein a short portion of at least the last element in said series of elements is coupled to a substantially U- shaped joint bridge member having an aperture in each of its two legs, said apertures vbeing of circular or square or any other suitable shape.

8. A series of structural elements according to claim 1, wherein a short portion of one of said elements is in the nature of a plate-like bearing member having a circular hole formed therein.

9. A series of structural elements according to claim 8, wherein said bearing member is provided with clamping means projecting slightly from its periphery.

10. A series of structural components according to claim 1, wherein the elements of said series of elements are of angular shape.

11. A series of structural elements according to claim 1, wherein the elements are formed of cast concrete.

12. A series of structural elements according to claim 4, wherein `said portions are formed of cast concrete.

13. A series of structural elements according to claim 7, wherein said bridge member is formed of plastics material such as elastically deformable polymerizates.

14. A series of structural elements according to claim 7, wherein said bridge member is formed of cast concrete.

15. A series of structural elements according to claim 8, wherein said bearing member is formed of plastics material such as elastically deformable polymerizates.

16. A series of structural elements according to claim 8, wherein said bearing member is formed of cast concrete.

References Cited UNITED STATES PATENTS 1,985,032 12/1934 Hoult 46-29 2,052,600 9/ 1936 Boss 46-16 XR 2,941,855 6/1960 Weill 287-54 FOREIGN PATENTS 27,672 12/ 1912 Great Britain.

937,251 3/1948 France.

735,945 8/ 1955 Great Britain.

JAMES T. MCCALL, Primary Examiner.

R. D. KRAUS, Assistant Examiner.

U.S. Cl. X.R. 46-25 

